I thought this thread was locked as well:)
I didn’t want to scroll back, but there was mention of ‘72 CR.
I can assure you no way I’ll be at 8.6? I think it was SCR.
With the .030 pistons it has now, 4 corner measurements sow .105-.095 with them at TDC. But that’s not off a centerlines, just deck to then ends on each side.
Using wallacaraxing CR calculator that take bore size into account, I’d need the decks at 9.585 vs 9.6 to be close to 8.1:1 SCR.
I have open chamber heads,
I could get the casting numbers but from what I gathered here and via the web they are “spec’ed at 72 cc’s.
Maybe the 8.6:1 was with a closed chamber head?
And after
@junkyardhero (and others) explained to me LSA and cylinder pressure I’ll be looking in the 106-108 range with a grinder.